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[A]: Phytotron is a device by which phot...

[A]: Phytotron is a device by which photolysis of water is created.
[R]: Phytotron is a method of keeping plants in natural light and temperature in houses

A

If both A and R are true and R is the correct explanation of A

B

If both A and R are true but R is not the correct explanation of A

C

If A is true and R is false

D

If both A and R are false

Text Solution

Verified by Experts

The correct Answer is:
D
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Knowledge Check

  • Perhaps the highest temperature material you will ever see is the sun's outer atmosphere, or corona. At a temperature of about 2 times 10^(6@)C " or " 3.6 times 10^(6@)F , the corona glows with a light that is literally unearthly. But because corona is also very thin, its light is rather faint. You can only see the corona during a total solar eclipse when the sun's disk is covered by the moon. What is the highest temperature which can be created on earth for a sufficiently long time ?

    A
    `1500^(@)C`
    B
    `2000^(@)C`
    C
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    D
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  • In the atmosphere, carbon dioxide is found in two forms, i.e., ^12CO_2 and ^14CO_2 . Plants absord CO_2 during photosynthesis in presence of chlorophyll, plants systhesise glucose 6CO_2 +6 H_2O rarr C_6H_12O_6 + 6O_2uarr Half life of ^14CO_2 is 5760 years. The analysis of wooden artifacts for ^14C and ^12C gives useful information for determination of its age. All living organisms, because of their constant exchange of Carbon dioxide with the surroundings have the same ratio of C-14 to C-12, i.e. 1.3xx10^-12 . When an organism dies, the C-14 in it keeps on decaying as follows: 6^14Crarr7^14N+(-1)^0e +Energy Thus, the ratio of C-14 and C-12 decreases with the passage of time. We can measure the proportion of C-14 in the remains of dead organism and determine how long ago it died. The method of carbon dating can be used to date anything made or organic matter, e.g., bone, skeleton, wood, etc. Using carbon dating, materials have been dated to about 50,000 years with accuracy. A piece of wood from an archeological source shows a C-14 activity which is 60% of the activity found in fresh wood today. The age of archeological sample will be:

    A
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    B
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    C
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    D
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